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Comment by caf | Hacker News Reader

There is a flying telescope built on a 747SP, a joint enterprise of NASA and the German space agency, called SOFIA. It is able to fly to see events like this that can only be observed from a limited range of locations.

https://www.abc.net.au/news/2019-02-01/sofia-flying-telescop...

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I think SOFIA is used mainly for Infrared astronomy. By flying above most of the atmosphere it can observe in the infrared, where Earth based telescopes are severely limited.

The purpose of SOFIA is to fly above as much of the water vapour in the atmosphere as possible to do astronomy in the far infrared and terrahertz regimes: frequencies that are absorbed by water. Near infrared astronomy can easily be done from the ground. As the grandparent mentioned, it is also used as a mobile telescope to do observations of stellar occultations. The purpose of this is to get a measure, for example, of Pluto's atmosphere as it passes in front of a star. I doubt it would be used for an occultation by an asteroid as you wouldn't gain anything by the measurement.

I suppose you could get information about the asteroid's shape?

Indeed they do. You can see some of the analysis here [1], by calculating the time period of the occultation and the transit location of the star across the body of the asteroid. I don't know how they account for rotation or how they so precisely know where the asteroid will be relative to the star.

[1] https://www.google.com/search?tbm=isch&sa=1&q=asteroid+shape...

That is an excellent article about SOFIA thanks heaps for sharing it.

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